docs: def export(self, nidm_version, export_dir):
          """
          Create prov entities and activities.
          """
          if nidm_version['major'] < 1 or \
                  (nidm_version['major'] == 1 and nidm_version['minor'] < 3):
              self.type = NIDM_DATA_SCALING
      # Create "Data" entity
          # FIXME: grand mean scaling?
          # FIXME: medianIntensity
          self.add_attributes((
              (PROV['type'], self.type),
              (PROV['type'], PROV['Collection']),
              (PROV['label'], self.label),
              (NIDM_GRAND_MEAN_SCALING, self.grand_mean_sc),
              (NIDM_TARGET_INTENSITY, self.target_intensity)))
  
          if nidm_version['major'] > 1 or \
                  (nidm_version['major'] == 1 and nidm_version['minor'] > 2):
              if self.mri_protocol is not None:
                  self.add_attributes(
                      [(NIDM_HAS_MRI_PROTOCOL, self.mri_protocol)])